10 
All machines, spouts, elevators, etc., should l)e left open to allow of free en- 
trance of gas. I'his gas is lighter than air ; it rises ; therefore, it would not 
1)6 safe for one to drop packages of cyanide into jars of acid in a hasement, and 
then endeavor to leave hy asccndiii<^ stairs. Hence, e\’en when we drop hy hand, 
we frequently string the hasement. 
U’hat Coiisfifiitcs Surress in Treating a Mill. It must he home in mind 
that a mill sufficiently infested to call for treatment necessarily contains many 
thousands of the moths in some stage. A fe\v "worms” or pupae, concealed in 
some crack on the side of a window or elsewhere may escape the deadly fumes, 
hnt the finding of five, ten, or twenty live Nvorms after the' fumigation hy no 
means indicates failure. Far from it for, eliminating all unfavorable conditions, 
it might take se\’eral \ ears for a mill to become sufficiently reinfested from tins 
source alone to need another treatment. 
1'he above is, in brief, the method of procedure in fumigating mills for the 
fionr moth. The gas is a safe and more efficient agent wdien used with care by 
those familiar with its nature. One good whiff of it, however, would prohahly 
he fatal to any human being, hcncc, its use should never be entrusted to one not 
faniiliar zeith it. Its presenee eon be deteeted ez'e)i in minute quantities by its 
odor zehieh resembles that of the kernel of peaeh pits. 
The writer is in receipt almost daily of statements from millers 
testifying- to the efificacy of this method; a few of these are repeated 
here : 
h'rom the owner of a badly infested mill ; 
“The work seems to have been a success, and we certainly could 
not have continued running- without the treatment. I have l)een around 
the mill this morning making a personal examination of the results of 
the work ; have taken out of spouts a large amount of webbing and 
worms, and on a careful examination do not hnd a single live worm or 
moth, and some of the masses in the spouts were i)ossibly an incli 
thick.” 
.Vnother mill owner, whose ])lant was ])erha])s one of the worst in 
this connection I had ever seen, says: 
“The process seems to be a most successful one where mills are 
infested with various ])ests.” 
Idle head miller of a seriously infested milling ])lant in Illinois 
writes after fumigation : 
“I have not seen one now in two months, and am keeping a sharj) 
lookout for them all the time. This seems a remarkable condition to 
one familiar with the premises and knowing how well they were estab- 
lished in the mill.” 
Another miller writes ; have been using hydrocyanic acid gas 
for a number of vears with verv satisfactorv results.” An Illinois iirm 
